In general, a digital unit and a radio unit are installed together in a single physical system of a communication base station. However, such a design of the base station has limitations in cell design optimization because it requires installing a base station including both of a radio unit and a digital unit at each cell. To overcome such a limitation, a plurality of antennas is connected to single base station to form a cell as necessary and to reduce coverage holes.
Such configuration of the base station may enable efficient cell design but has a limitation to maximize system capacity. Accordingly, there is a demand to develop a new structure and a new transfer method for a base station to maximize radio capacity.